Fuel-pump



0. W. PFEFFER.

FUEL PUMP.

. 1]- I L 349,@@@ Patented Aug. 10, 1920.

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Specification of Letters Patent.

Patented Aug. 10, 1920,.

Application filed September 14, 1917. Serial No. 191,425.

To all whom it may concern;

Be it known that I, O'soAR PFEFFER, a citizen of the United States,residing in St. Louis, issouri, have invented the following describedImprovements in Fuelumps.

pressure pump mechanism such as used for fuel oil injection orlubricating purposes in internal combustion engines, and its object isto simplify the structure and cheapen the cost of manufacture of suchpumps as well as to improve the facility for inspection and repair. Theinvention consists in an organization of the pump chamber and pumpvalves in a structure formed separately from the main pump body butremovabl secured therein, whereby the said main bo y can be made of castiron, whichis cheap, and the inserted body of denser metal such asrolled or cast bronze or steel forging, which is non-porous and notlikely to permit leakage through its walls as in the case of cast ironunder high pressure. The invention also consists in the generalarrangement of parts as herein described which further enhances theutility and convenience of pump mechanism incorporating this invention.

In the drawing,

Figure l is a longitudinal section through I T a portion of the maincast ironpumpb0 and through the axis of the dense metal inserted body inposition therein;

Fig. 2 is a cross section through the outlet Ipofit showing its relationto the inserted The main pump body marked 1, is cast of any desiredexternal shape such as may be suited to the particular purpose for whichthe pump isnsed and for which reason onl part of it is illustrated 1nthe drawing. It contains in the present case, an entrance chamber 2 forthe oil supply incoming from the pipe 3 which chamber is closed by aremovable cover plate 4, and it also contains a plunger chamber 5 inwhich the pump plunger 6 is reciprocated by any suitable means, notshown. The plunger chamber 5 intersects a chamber 7 which extendstransversely thereto-into the entrance chamber 2 and which is ground toa conical taper of low pitch as indicated. The inserted body 8 is groundto a corresponding conical shape and seated firmly in the taperedchamber 7 inserted body 8.

by means of a clamp member such as the ring nut 9 which is screwed intothe cast lron body 1 and against the shoulder of the The said insertedbody is made of some of the denser metals above alluded to and containswithin itself the suc- The invention is an improvement in high tion andoutlet valves of the pump and the passages leading to and from them. Theinlet valve 10 of any suitable type is seated in the lower part of thebody 8 and the fuel body from which leads the delivered charge. The

point a pipe connection fuel to its point of dissuctlon valve end of theinsubject to engagement by one arm of an eccentrically fulcrumed bellcrank 18, the other arm of which is operated by a push rod 19reciprocatin in unison with the pump plunger 6. his rod acting through.the bell crank opens the suctionvalve and, receding, permits it toclose., By rotating the shaft 20.which carries the bell crank fulcrumeccentrically thereon, the position of the bell crank may be varied withrelation to the valve so as to vary the time of its closing and therebyvary the amount of fuel oil delivered through the outlet passage, thismanner of fuel control being common in the art. It will be observed thatin the present construction the inserted body 8 holds the suction valvein the correct position for regulation by the bell crank, being at thesame time removable with said body. The ground joint'between theinserted and the main body uniform metallic contact which givesreinforcement to the relatively thin walls of the affords a' insertedvalve holder while the density of v the material of which the same ismade prethick walls suited to prevent leakage of the vents leakagetherethrough and thereby inliquid therethrough, a tapered chamber suresa clean exterior for the apparatus forming a communication between saidwhen in use. The plunger chamber 5 is plunger chamber and passages and atapered 5 formed entirely in the cast bodyvbut leakage valve holder ofdenser metal occupying said 20 through its wall is minimized by reasonof chamber and containing inlet and outlet the greater thickness ofmetal which is convalves controlling the communications from venientlyused in this part of the structure. said plunger chamber to saidpassages re- 1 Claim. 7 spectively, the walls of said valve holder, 10The combination with a high pressure where exposed to the liquid underpressure, 25 pump body of cast ironhaving formed therebeing relativelythinner than the cast iron in a plunger chamber and passages for thewalls of said chamber.

inlet and outlet of the liquid to-bepumped, In testimony whereof, I havesigned this said chamber and passages where exposed to specification. I15 the fluid under pressure having relatively OSCAR W. PFEFFER.

